From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sat, 16 Apr 2005 15:20:36 -0700 Subject: Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip! --- arch/s390/kernel/smp.c | 840 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 840 insertions(+) create mode 100644 arch/s390/kernel/smp.c (limited to 'arch/s390/kernel/smp.c') diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c new file mode 100644 index 000000000000..fdfcf0488b49 --- /dev/null +++ b/arch/s390/kernel/smp.c @@ -0,0 +1,840 @@ +/* + * arch/s390/kernel/smp.c + * + * S390 version + * Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation + * Author(s): Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com), + * Martin Schwidefsky (schwidefsky@de.ibm.com) + * Heiko Carstens (heiko.carstens@de.ibm.com) + * + * based on other smp stuff by + * (c) 1995 Alan Cox, CymruNET Ltd + * (c) 1998 Ingo Molnar + * + * We work with logical cpu numbering everywhere we can. The only + * functions using the real cpu address (got from STAP) are the sigp + * functions. For all other functions we use the identity mapping. + * That means that cpu_number_map[i] == i for every cpu. cpu_number_map is + * used e.g. to find the idle task belonging to a logical cpu. Every array + * in the kernel is sorted by the logical cpu number and not by the physical + * one which is causing all the confusion with __cpu_logical_map and + * cpu_number_map in other architectures. + */ + +#include +#include + +#include +#include +#include +#include + +#include +#include +#include +#include + +#include +#include +#include +#include +#include +#include + +/* prototypes */ + +extern volatile int __cpu_logical_map[]; + +/* + * An array with a pointer the lowcore of every CPU. + */ + +struct _lowcore *lowcore_ptr[NR_CPUS]; + +cpumask_t cpu_online_map; +cpumask_t cpu_possible_map; + +static struct task_struct *current_set[NR_CPUS]; + +EXPORT_SYMBOL(cpu_online_map); + +/* + * Reboot, halt and power_off routines for SMP. + */ +extern char vmhalt_cmd[]; +extern char vmpoff_cmd[]; + +extern void reipl(unsigned long devno); + +static void smp_ext_bitcall(int, ec_bit_sig); +static void smp_ext_bitcall_others(ec_bit_sig); + +/* + * Structure and data for smp_call_function(). This is designed to minimise + * static memory requirements. It also looks cleaner. + */ +static DEFINE_SPINLOCK(call_lock); + +struct call_data_struct { + void (*func) (void *info); + void *info; + atomic_t started; + atomic_t finished; + int wait; +}; + +static struct call_data_struct * call_data; + +/* + * 'Call function' interrupt callback + */ +static void do_call_function(void) +{ + void (*func) (void *info) = call_data->func; + void *info = call_data->info; + int wait = call_data->wait; + + atomic_inc(&call_data->started); + (*func)(info); + if (wait) + atomic_inc(&call_data->finished); +} + +/* + * this function sends a 'generic call function' IPI to all other CPUs + * in the system. + */ + +int smp_call_function (void (*func) (void *info), void *info, int nonatomic, + int wait) +/* + * [SUMMARY] Run a function on all other CPUs. + * The function to run. This must be fast and non-blocking. + * An arbitrary pointer to pass to the function. + * currently unused. + * If true, wait (atomically) until function has completed on other CPUs. + * [RETURNS] 0 on success, else a negative status code. Does not return until + * remote CPUs are nearly ready to execute <> or are or have executed. + * + * You must not call this function with disabled interrupts or from a + * hardware interrupt handler or from a bottom half handler. + */ +{ + struct call_data_struct data; + int cpus = num_online_cpus()-1; + + if (cpus <= 0) + return 0; + + /* Can deadlock when called with interrupts disabled */ + WARN_ON(irqs_disabled()); + + data.func = func; + data.info = info; + atomic_set(&data.started, 0); + data.wait = wait; + if (wait) + atomic_set(&data.finished, 0); + + spin_lock(&call_lock); + call_data = &data; + /* Send a message to all other CPUs and wait for them to respond */ + smp_ext_bitcall_others(ec_call_function); + + /* Wait for response */ + while (atomic_read(&data.started) != cpus) + cpu_relax(); + + if (wait) + while (atomic_read(&data.finished) != cpus) + cpu_relax(); + spin_unlock(&call_lock); + + return 0; +} + +/* + * Call a function on one CPU + * cpu : the CPU the function should be executed on + * + * You must not call this function with disabled interrupts or from a + * hardware interrupt handler. You may call it from a bottom half. + * + * It is guaranteed that the called function runs on the specified CPU, + * preemption is disabled. + */ +int smp_call_function_on(void (*func) (void *info), void *info, + int nonatomic, int wait, int cpu) +{ + struct call_data_struct data; + int curr_cpu; + + if (!cpu_online(cpu)) + return -EINVAL; + + /* disable preemption for local function call */ + curr_cpu = get_cpu(); + + if (curr_cpu == cpu) { + /* direct call to function */ + func(info); + put_cpu(); + return 0; + } + + data.func = func; + data.info = info; + atomic_set(&data.started, 0); + data.wait = wait; + if (wait) + atomic_set(&data.finished, 0); + + spin_lock_bh(&call_lock); + call_data = &data; + smp_ext_bitcall(cpu, ec_call_function); + + /* Wait for response */ + while (atomic_read(&data.started) != 1) + cpu_relax(); + + if (wait) + while (atomic_read(&data.finished) != 1) + cpu_relax(); + + spin_unlock_bh(&call_lock); + put_cpu(); + return 0; +} +EXPORT_SYMBOL(smp_call_function_on); + +static inline void do_send_stop(void) +{ + int cpu, rc; + + /* stop all processors */ + for_each_online_cpu(cpu) { + if (cpu == smp_processor_id()) + continue; + do { + rc = signal_processor(cpu, sigp_stop); + } while (rc == sigp_busy); + } +} + +static inline void do_store_status(void) +{ + int cpu, rc; + + /* store status of all processors in their lowcores (real 0) */ + for_each_online_cpu(cpu) { + if (cpu == smp_processor_id()) + continue; + do { + rc = signal_processor_p( + (__u32)(unsigned long) lowcore_ptr[cpu], cpu, + sigp_store_status_at_address); + } while(rc == sigp_busy); + } +} + +/* + * this function sends a 'stop' sigp to all other CPUs in the system. + * it goes straight through. + */ +void smp_send_stop(void) +{ + /* write magic number to zero page (absolute 0) */ + lowcore_ptr[smp_processor_id()]->panic_magic = __PANIC_MAGIC; + + /* stop other processors. */ + do_send_stop(); + + /* store status of other processors. */ + do_store_status(); +} + +/* + * Reboot, halt and power_off routines for SMP. + */ + +static void do_machine_restart(void * __unused) +{ + int cpu; + static atomic_t cpuid = ATOMIC_INIT(-1); + + if (atomic_compare_and_swap(-1, smp_processor_id(), &cpuid)) + signal_processor(smp_processor_id(), sigp_stop); + + /* Wait for all other cpus to enter stopped state */ + for_each_online_cpu(cpu) { + if (cpu == smp_processor_id()) + continue; + while(!smp_cpu_not_running(cpu)) + cpu_relax(); + } + + /* Store status of other cpus. */ + do_store_status(); + + /* + * Finally call reipl. Because we waited for all other + * cpus to enter this function we know that they do + * not hold any s390irq-locks (the cpus have been + * interrupted by an external interrupt and s390irq + * locks are always held disabled). + */ + if (MACHINE_IS_VM) + cpcmd ("IPL", NULL, 0); + else + reipl (0x10000 | S390_lowcore.ipl_device); +} + +void machine_restart_smp(char * __unused) +{ + on_each_cpu(do_machine_restart, NULL, 0, 0); +} + +static void do_wait_for_stop(void) +{ + unsigned long cr[16]; + + __ctl_store(cr, 0, 15); + cr[0] &= ~0xffff; + cr[6] = 0; + __ctl_load(cr, 0, 15); + for (;;) + enabled_wait(); +} + +static void do_machine_halt(void * __unused) +{ + static atomic_t cpuid = ATOMIC_INIT(-1); + + if (atomic_compare_and_swap(-1, smp_processor_id(), &cpuid) == 0) { + smp_send_stop(); + if (MACHINE_IS_VM && strlen(vmhalt_cmd) > 0) + cpcmd(vmhalt_cmd, NULL, 0); + signal_processor(smp_processor_id(), + sigp_stop_and_store_status); + } + do_wait_for_stop(); +} + +void machine_halt_smp(void) +{ + on_each_cpu(do_machine_halt, NULL, 0, 0); +} + +static void do_machine_power_off(void * __unused) +{ + static atomic_t cpuid = ATOMIC_INIT(-1); + + if (atomic_compare_and_swap(-1, smp_processor_id(), &cpuid) == 0) { + smp_send_stop(); + if (MACHINE_IS_VM && strlen(vmpoff_cmd) > 0) + cpcmd(vmpoff_cmd, NULL, 0); + signal_processor(smp_processor_id(), + sigp_stop_and_store_status); + } + do_wait_for_stop(); +} + +void machine_power_off_smp(void) +{ + on_each_cpu(do_machine_power_off, NULL, 0, 0); +} + +/* + * This is the main routine where commands issued by other + * cpus are handled. + */ + +void do_ext_call_interrupt(struct pt_regs *regs, __u16 code) +{ + unsigned long bits; + + /* + * handle bit signal external calls + * + * For the ec_schedule signal we have to do nothing. All the work + * is done automatically when we return from the interrupt. + */ + bits = xchg(&S390_lowcore.ext_call_fast, 0); + + if (test_bit(ec_call_function, &bits)) + do_call_function(); +} + +/* + * Send an external call sigp to another cpu and return without waiting + * for its completion. + */ +static void smp_ext_bitcall(int cpu, ec_bit_sig sig) +{ + /* + * Set signaling bit in lowcore of target cpu and kick it + */ + set_bit(sig, (unsigned long *) &lowcore_ptr[cpu]->ext_call_fast); + while(signal_processor(cpu, sigp_external_call) == sigp_busy) + udelay(10); +} + +/* + * Send an external call sigp to every other cpu in the system and + * return without waiting for its completion. + */ +static void smp_ext_bitcall_others(ec_bit_sig sig) +{ + int cpu; + + for_each_online_cpu(cpu) { + if (cpu == smp_processor_id()) + continue; + /* + * Set signaling bit in lowcore of target cpu and kick it + */ + set_bit(sig, (unsigned long *) &lowcore_ptr[cpu]->ext_call_fast); + while (signal_processor(cpu, sigp_external_call) == sigp_busy) + udelay(10); + } +} + +#ifndef CONFIG_ARCH_S390X +/* + * this function sends a 'purge tlb' signal to another CPU. + */ +void smp_ptlb_callback(void *info) +{ + local_flush_tlb(); +} + +void smp_ptlb_all(void) +{ + on_each_cpu(smp_ptlb_callback, NULL, 0, 1); +} +EXPORT_SYMBOL(smp_ptlb_all); +#endif /* ! CONFIG_ARCH_S390X */ + +/* + * this function sends a 'reschedule' IPI to another CPU. + * it goes straight through and wastes no time serializing + * anything. Worst case is that we lose a reschedule ... + */ +void smp_send_reschedule(int cpu) +{ + smp_ext_bitcall(cpu, ec_schedule); +} + +/* + * parameter area for the set/clear control bit callbacks + */ +typedef struct +{ + __u16 start_ctl; + __u16 end_ctl; + unsigned long orvals[16]; + unsigned long andvals[16]; +} ec_creg_mask_parms; + +/* + * callback for setting/clearing control bits + */ +void smp_ctl_bit_callback(void *info) { + ec_creg_mask_parms *pp; + unsigned long cregs[16]; + int i; + + pp = (ec_creg_mask_parms *) info; + __ctl_store(cregs[pp->start_ctl], pp->start_ctl, pp->end_ctl); + for (i = pp->start_ctl; i <= pp->end_ctl; i++) + cregs[i] = (cregs[i] & pp->andvals[i]) | pp->orvals[i]; + __ctl_load(cregs[pp->start_ctl], pp->start_ctl, pp->end_ctl); +} + +/* + * Set a bit in a control register of all cpus + */ +void smp_ctl_set_bit(int cr, int bit) { + ec_creg_mask_parms parms; + + parms.start_ctl = cr; + parms.end_ctl = cr; + parms.orvals[cr] = 1 << bit; + parms.andvals[cr] = -1L; + preempt_disable(); + smp_call_function(smp_ctl_bit_callback, &parms, 0, 1); + __ctl_set_bit(cr, bit); + preempt_enable(); +} + +/* + * Clear a bit in a control register of all cpus + */ +void smp_ctl_clear_bit(int cr, int bit) { + ec_creg_mask_parms parms; + + parms.start_ctl = cr; + parms.end_ctl = cr; + parms.orvals[cr] = 0; + parms.andvals[cr] = ~(1L << bit); + preempt_disable(); + smp_call_function(smp_ctl_bit_callback, &parms, 0, 1); + __ctl_clear_bit(cr, bit); + preempt_enable(); +} + +/* + * Lets check how many CPUs we have. + */ + +void +__init smp_check_cpus(unsigned int max_cpus) +{ + int cpu, num_cpus; + __u16 boot_cpu_addr; + + /* + * cpu 0 is the boot cpu. See smp_prepare_boot_cpu. + */ + + boot_cpu_addr = S390_lowcore.cpu_data.cpu_addr; + current_thread_info()->cpu = 0; + num_cpus = 1; + for (cpu = 0; cpu <= 65535 && num_cpus < max_cpus; cpu++) { + if ((__u16) cpu == boot_cpu_addr) + continue; + __cpu_logical_map[num_cpus] = (__u16) cpu; + if (signal_processor(num_cpus, sigp_sense) == + sigp_not_operational) + continue; + cpu_set(num_cpus, cpu_present_map); + num_cpus++; + } + + for (cpu = 1; cpu < max_cpus; cpu++) + cpu_set(cpu, cpu_possible_map); + + printk("Detected %d CPU's\n",(int) num_cpus); + printk("Boot cpu address %2X\n", boot_cpu_addr); +} + +/* + * Activate a secondary processor. + */ +extern void init_cpu_timer(void); +extern void init_cpu_vtimer(void); +extern int pfault_init(void); +extern void pfault_fini(void); + +int __devinit start_secondary(void *cpuvoid) +{ + /* Setup the cpu */ + cpu_init(); + /* init per CPU timer */ + init_cpu_timer(); +#ifdef CONFIG_VIRT_TIMER + init_cpu_vtimer(); +#endif +#ifdef CONFIG_PFAULT + /* Enable pfault pseudo page faults on this cpu. */ + pfault_init(); +#endif + /* Mark this cpu as online */ + cpu_set(smp_processor_id(), cpu_online_map); + /* Switch on interrupts */ + local_irq_enable(); + /* Print info about this processor */ + print_cpu_info(&S390_lowcore.cpu_data); + /* cpu_idle will call schedule for us */ + cpu_idle(); + return 0; +} + +static void __init smp_create_idle(unsigned int cpu) +{ + struct task_struct *p; + + /* + * don't care about the psw and regs settings since we'll never + * reschedule the forked task. + */ + p = fork_idle(cpu); + if (IS_ERR(p)) + panic("failed fork for CPU %u: %li", cpu, PTR_ERR(p)); + current_set[cpu] = p; +} + +/* Reserving and releasing of CPUs */ + +static DEFINE_SPINLOCK(smp_reserve_lock); +static int smp_cpu_reserved[NR_CPUS]; + +int +smp_get_cpu(cpumask_t cpu_mask) +{ + unsigned long flags; + int cpu; + + spin_lock_irqsave(&smp_reserve_lock, flags); + /* Try to find an already reserved cpu. */ + for_each_cpu_mask(cpu, cpu_mask) { + if (smp_cpu_reserved[cpu] != 0) { + smp_cpu_reserved[cpu]++; + /* Found one. */ + goto out; + } + } + /* Reserve a new cpu from cpu_mask. */ + for_each_cpu_mask(cpu, cpu_mask) { + if (cpu_online(cpu)) { + smp_cpu_reserved[cpu]++; + goto out; + } + } + cpu = -ENODEV; +out: + spin_unlock_irqrestore(&smp_reserve_lock, flags); + return cpu; +} + +void +smp_put_cpu(int cpu) +{ + unsigned long flags; + + spin_lock_irqsave(&smp_reserve_lock, flags); + smp_cpu_reserved[cpu]--; + spin_unlock_irqrestore(&smp_reserve_lock, flags); +} + +static inline int +cpu_stopped(int cpu) +{ + __u32 status; + + /* Check for stopped state */ + if (signal_processor_ps(&status, 0, cpu, sigp_sense) == sigp_status_stored) { + if (status & 0x40) + return 1; + } + return 0; +} + +/* Upping and downing of CPUs */ + +int +__cpu_up(unsigned int cpu) +{ + struct task_struct *idle; + struct _lowcore *cpu_lowcore; + struct stack_frame *sf; + sigp_ccode ccode; + int curr_cpu; + + for (curr_cpu = 0; curr_cpu <= 65535; curr_cpu++) { + __cpu_logical_map[cpu] = (__u16) curr_cpu; + if (cpu_stopped(cpu)) + break; + } + + if (!cpu_stopped(cpu)) + return -ENODEV; + + ccode = signal_processor_p((__u32)(unsigned long)(lowcore_ptr[cpu]), + cpu, sigp_set_prefix); + if (ccode){ + printk("sigp_set_prefix failed for cpu %d " + "with condition code %d\n", + (int) cpu, (int) ccode); + return -EIO; + } + + idle = current_set[cpu]; + cpu_lowcore = lowcore_ptr[cpu]; + cpu_lowcore->kernel_stack = (unsigned long) + idle->thread_info + (THREAD_SIZE); + sf = (struct stack_frame *) (cpu_lowcore->kernel_stack + - sizeof(struct pt_regs) + - sizeof(struct stack_frame)); + memset(sf, 0, sizeof(struct stack_frame)); + sf->gprs[9] = (unsigned long) sf; + cpu_lowcore->save_area[15] = (unsigned long) sf; + __ctl_store(cpu_lowcore->cregs_save_area[0], 0, 15); + __asm__ __volatile__("stam 0,15,0(%0)" + : : "a" (&cpu_lowcore->access_regs_save_area) + : "memory"); + cpu_lowcore->percpu_offset = __per_cpu_offset[cpu]; + cpu_lowcore->current_task = (unsigned long) idle; + cpu_lowcore->cpu_data.cpu_nr = cpu; + eieio(); + signal_processor(cpu,sigp_restart); + + while (!cpu_online(cpu)) + cpu_relax(); + return 0; +} + +int +__cpu_disable(void) +{ + unsigned long flags; + ec_creg_mask_parms cr_parms; + + spin_lock_irqsave(&smp_reserve_lock, flags); + if (smp_cpu_reserved[smp_processor_id()] != 0) { + spin_unlock_irqrestore(&smp_reserve_lock, flags); + return -EBUSY; + } + +#ifdef CONFIG_PFAULT + /* Disable pfault pseudo page faults on this cpu. */ + pfault_fini(); +#endif + + /* disable all external interrupts */ + + cr_parms.start_ctl = 0; + cr_parms.end_ctl = 0; + cr_parms.orvals[0] = 0; + cr_parms.andvals[0] = ~(1<<15 | 1<<14 | 1<<13 | 1<<12 | + 1<<11 | 1<<10 | 1<< 6 | 1<< 4); + smp_ctl_bit_callback(&cr_parms); + + /* disable all I/O interrupts */ + + cr_parms.start_ctl = 6; + cr_parms.end_ctl = 6; + cr_parms.orvals[6] = 0; + cr_parms.andvals[6] = ~(1<<31 | 1<<30 | 1<<29 | 1<<28 | + 1<<27 | 1<<26 | 1<<25 | 1<<24); + smp_ctl_bit_callback(&cr_parms); + + /* disable most machine checks */ + + cr_parms.start_ctl = 14; + cr_parms.end_ctl = 14; + cr_parms.orvals[14] = 0; + cr_parms.andvals[14] = ~(1<<28 | 1<<27 | 1<<26 | 1<<25 | 1<<24); + smp_ctl_bit_callback(&cr_parms); + + spin_unlock_irqrestore(&smp_reserve_lock, flags); + return 0; +} + +void +__cpu_die(unsigned int cpu) +{ + /* Wait until target cpu is down */ + while (!smp_cpu_not_running(cpu)) + cpu_relax(); + printk("Processor %d spun down\n", cpu); +} + +void +cpu_die(void) +{ + idle_task_exit(); + signal_processor(smp_processor_id(), sigp_stop); + BUG(); + for(;;); +} + +/* + * Cycle through the processors and setup structures. + */ + +void __init smp_prepare_cpus(unsigned int max_cpus) +{ + unsigned long stack; + unsigned int cpu; + int i; + + /* request the 0x1202 external interrupt */ + if (register_external_interrupt(0x1202, do_ext_call_interrupt) != 0) + panic("Couldn't request external interrupt 0x1202"); + smp_check_cpus(max_cpus); + memset(lowcore_ptr,0,sizeof(lowcore_ptr)); + /* + * Initialize prefix pages and stacks for all possible cpus + */ + print_cpu_info(&S390_lowcore.cpu_data); + + for(i = 0; i < NR_CPUS; i++) { + if (!cpu_possible(i)) + continue; + lowcore_ptr[i] = (struct _lowcore *) + __get_free_pages(GFP_KERNEL|GFP_DMA, + sizeof(void*) == 8 ? 1 : 0); + stack = __get_free_pages(GFP_KERNEL,ASYNC_ORDER); + if (lowcore_ptr[i] == NULL || stack == 0ULL) + panic("smp_boot_cpus failed to allocate memory\n"); + + *(lowcore_ptr[i]) = S390_lowcore; + lowcore_ptr[i]->async_stack = stack + (ASYNC_SIZE); +#ifdef CONFIG_CHECK_STACK + stack = __get_free_pages(GFP_KERNEL,0); + if (stack == 0ULL) + panic("smp_boot_cpus failed to allocate memory\n"); + lowcore_ptr[i]->panic_stack = stack + (PAGE_SIZE); +#endif + } + set_prefix((u32)(unsigned long) lowcore_ptr[smp_processor_id()]); + + for_each_cpu(cpu) + if (cpu != smp_processor_id()) + smp_create_idle(cpu); +} + +void __devinit smp_prepare_boot_cpu(void) +{ + BUG_ON(smp_processor_id() != 0); + + cpu_set(0, cpu_online_map); + cpu_set(0, cpu_present_map); + cpu_set(0, cpu_possible_map); + S390_lowcore.percpu_offset = __per_cpu_offset[0]; + current_set[0] = current; +} + +void smp_cpus_done(unsigned int max_cpus) +{ + cpu_present_map = cpu_possible_map; +} + +/* + * the frequency of the profiling timer can be changed + * by writing a multiplier value into /proc/profile. + * + * usually you want to run this on all CPUs ;) + */ +int setup_profiling_timer(unsigned int multiplier) +{ + return 0; +} + +static DEFINE_PER_CPU(struct cpu, cpu_devices); + +static int __init topology_init(void) +{ + int cpu; + int ret; + + for_each_cpu(cpu) { + ret = register_cpu(&per_cpu(cpu_devices, cpu), cpu, NULL); + if (ret) + printk(KERN_WARNING "topology_init: register_cpu %d " + "failed (%d)\n", cpu, ret); + } + return 0; +} + +subsys_initcall(topology_init); + +EXPORT_SYMBOL(cpu_possible_map); +EXPORT_SYMBOL(lowcore_ptr); +EXPORT_SYMBOL(smp_ctl_set_bit); +EXPORT_SYMBOL(smp_ctl_clear_bit); +EXPORT_SYMBOL(smp_call_function); +EXPORT_SYMBOL(smp_get_cpu); +EXPORT_SYMBOL(smp_put_cpu); + -- cgit v1.2.3